Jenki

Since the last blog, a lot has happened in a relatively short time. The last blog was Stage 1 of the Amenity block, needing cladding and the roof, and as I'm sat here early in the morning , with the wind constantly blowing 20MPH, 2mm rain p/h. and a toasty 8 deg. inside the static, which is our home now - yey. The Cabins are complete. A lot of work and a move thrown in to the mix since the middle of August. The cabins are stick built on site, under the supervision of Building control, this means that the insulation and detailing falls within the small building regulations and thus U values are quite tight. The positive is that they will be relatively cheap to heat year round. The downside was we spent a lot more on insulation. The process was the same as the amenity block, the foundation slab was cast, and the floor insulation (120mm PIR) was sat on top of this and a radon barrier with floating chipboard on top. 6inch walls with glass wool insulation. Due to the extreme cost variations and difficulty getting hold of Frame therm 32, the walls were filled with a mixture of Frame therm 32 & 40, I managed to get some at £18/ roll in Bradford and dragged it up with me, collecting some over ordered frame therm40, from Stirling on the way (thanks Market place). The bottom line was that I needed to add 25mm PIR inside to get the 0.21U required. The Roof was 120mm fibre glass coated PIR, with Firestone rubber bonded direct. The original plans was to clad the pods in Black Metal, but after some thoughts through BH (Salt in the air etc, we changed to Scottish Larch. We had 300, 4.8M lengths delivered from Huntly area. Mandy spent around 2 weeks solid staining these both sides and edges black. she was amazing, this was not an easy task. I think I painted 3/4 of 1 plank before I was off doing something else. The Orange look would have been too harsh, so we decided to stain them , and hopefully as the Larch ages and the stain fades they will eventually take on the natural look of Larch. Another tweak to the design was to cut the corner off the bathroom. allowing for 2 double beds, thinking that as our customers will in the main be only staying for a day or two, the bed was more important than sitting areas. My biggest concern was heating and hot water. I've asked on here before, and was thinking of using a 300l UVC, but was never happy this would supply enough hot water for two cabins and up to 10 people. - so either the expense of a Heat pump or direct immersion. I had laid 20mm MDPE pipe x 2 to each cabin from the amenity block. for the H&C supply. We bit the bullet and decided to supply the hot water via 2 off Cointra CPA11 open flue caravan heaters (LPG), I was concerned if the temperature would be ok, especially as the water travels between 3 & 6M underground . This was compounded further, later on, as we started having problems with the same heater in out static. Low temperature HW and problems when the wind picked up over 15MPH. Too late to worry, money was spent and It was suck it and see. Fitting the Open Flue heaters in the Amenity block created another issue, so we have ended up with a little extension on the side of amenity block that houses the two heater, basically its like they are outside, but inside. I have insulated them, but I will have to add a small heater with PID control (Job to do) to ensure the water does not freeze inside the boilers. For the hot water I fed 10mm PB pipe inside the MDPE pipe and hope the flow rates and temperature would work.... (I thought about asking on here, but sometimes you have to bite the bullet and see) We have installed UPVC DG windows, and I created MDF reveal liners, this allowed for the plaster boards to be fitted flush to the liners, with face mouldings to finish. I taped and jointed the PB, but to be honest it was a pain, due to the number of butt joints, on a couple of occasions I nearly went and bought some Multi finish. In general were happy with the finish, but it has confirmed that this WONT be happening on the house build. Mandy wanted a feature wall (interior design is where I stop), and the en-suite seemed to be a good place for this. We had just enough Larch left over, so Mandy cut and ripped this down, sanded one face and painted in various contrasting (I think that is what she said) colours. I helped a little with the first row or two install, as it does have some 22.55deg bevels, then I was back to to the other cabin sanding and filling. Due to the success of the Air to Air HP in the static, we decided to install the same in the cabins, this way we know the heat all year round will work. As this was a little after thought - external cladding was complete, I had to be creative with the internal pipe run, I created a box / shelf which can be seen in the photos below, this now acts as a cup holder with some cup hooks. The Bathrooms were clad with shower wall cladding. a Boxed in WC allows for all the utilities to enter and also houses the Wireless access point, which is powered POE. from the amenity block. Once the bathrooms were fitted, it was time to see if the HW works. Its a resounding yes. we had -4deg (This is how I know I need to stop the boilers freezing). but once I'd managed to thaw the boiler out, we were getting 40Deg in the cabins. The showers are not power showers, but they work really well, better than an electric shower. and heat up time is around 35 - 40 sec. The boilers have worked in 30MPH winds, so the issues with our static are just that and I'm still exploring the why. As we stand today 1 cabin is ready to let, and we are waiting delivery of 2 beds for the other cabin. 200m of livestock fencing in the new year will see this side of the project complete.

+1. I've built 2 cabins in Scotland, the walls needed 140mm frame therm and 25mm PIR to comply.

On my planned build I was thinking similar, but I see massive issues with getting this airtight ( planned camber truss and a few attic truss for storage) I'm now leaning to moving to standard truss and cold roof. The MVHR ducts will be below the insulation, and I was thinking of adding a 75mm service void at the ceiling to run pipes/ cables minimising the penetrations to the cold loft and airtight membrane.

If you do the floor, why not consider a floating timber floor, more insulation no concrete so a little cleaner. You will need to ensure the base is flat. But 150mm of PIR (OR 200MM EPS) would have a great impact. You could still add UFH.

WC connections are usually 180mm on centre. I think all is ok. and if your paying a plumber, its his issue anyway?

I fitted 3 of these now well this 1 and 2 others.

No. But more as I changed the plans to heat water for my cabins, I've gone for LPG gas water heaters as I didn't want them to run out of water. And heating the cabins with an Air 2 Air HP. Still thinking about these for the house but that's not starting till next year.

2.5MM t&e will handle around 26A (6KW), way past the 3.6KW load. Any bigger is a waste of money.

This was my plan, the Polysteel blocks are 600mm high, so strip footing (although the area has been excavated to bedrock.), then 1 course of ICF block to DPC, 300mm EPS on MOT for the slab.

@Russell griffiths. you didn't mis understand. Labour is me and the mrs, so i'm ignoring this. either way. Concrete pump this high up in the highlands is far from cheap but I've got a cost. Timber frame was going to be DIY insulated foundation, if i go for ICF then ill use ICF block to get to DPM (that's included in the price, as well as structural calcs) so I will save on the reinforcement, and EPS300 costs. not great savings but they all add up. Please comment from your experience with my thoughts on approach. Bracing will be DIY with timber and some adjustment hardware. and I'll pour the concrete from scaffolding on the external. The scaffold will assist with the bracing. I'll reuse the timber bracing for studwork. The way I see it and the costs, I'll get ICF structure to wall plate / gables for 15K. (this will have a u value of 0.13 for walls, and 0.11 for slab (300mm EPS) and minimal thermal bridge. With timber frame I will then need to start on airtightness for the walls, battens for service cavity etc. so yes a little more expensive than timber frame , but not massively. and having experienced a few weeks of the weather up here toward winter, I'm feeling better about a solid lump of concrete.

If DB2 only supplies (I Assume DB3) then change to switch fuse as @ProDave mentions. Then it won't trip as its just a fuse. but then the cable supplying DB3, (do you know what cable type it is?) is only protected with a big fuse - hence the + 1 for upgrading to SWA. - but this does not necessarily fix an issue in DB3. as DB 3 is a new CU have you got the test results for it? This could be tripping due to brown outs, surges in O/Head power lines, many reasons really. DB2 which causes the problem you mention the left or right trip? so either the RCD trips, or the MCB trips. to me it does point to an issues with A, the supply cable to DB3, (under size, failing insulation / damp) B, a circuit in DB3 - as again I'm assuming DB2 has a standard RCD, so it trips here first

652 miles down the road for me😂

My biggest concern would be what is at the back of the walls. Is there any tanking / damp proof membrane between the soil and the new block? If not, then the blocks will soak up the moisture and WILL come through to the front. If you render, then as @ProDave , suggests the render will pop off or at least blister before failing. If above could be an issuer, you could consider securing fence panels to the walls? or cladding. Steps could be paving / tiles.

IP68

Yep. IP56 as a minimum As you point out IP55 and IP65 give the same level of water protection.

Have you got land drainage around the base of the raft? Then you would want pea gravel or similar to act as a french drain

Personally wouldn't use IP 55 rated as an external consumer unit. Not guaranteed to survive driven rain etc. It is not classed as waterproof. A bit like a fold away cagoule 😂

Have you any details on the lagoon design? I've not researched this yet, but I'm finding that on out site It might be prudent for us to hold some water back. I was planning RWH for the house, and the latest rain has confirmed I need to do something, as the rubble drain for our treatment plant has backed up recently 🤔 I've got about 4 acres of field draining towards the coast past my treatment plant and not getting past my new track, so currently pumping this to help it on its way to the sea. I've got some more stone on the way to bring the level of my track back to the original field level, so it doesn't pool.

Generally soil pipes use rest bends. (A long radius with a foot). Gives the pipe extra support, I've seen people use long radius bends, but might be worth checking with BC. The pipes usually extend above FFL and capped to stop concrete entering the system. It's also a good idea to pressure test all this before the pour. ( In Scotland they will insist on the test.)

Thanks. Looks fantastic.

@Happy Valley, good to see someone has been there first.. how were the reveals for doors / windows catered for ? any photos of that? thanks in advance

My Budget is tight, and I plan (planned) stick built on site by me, and my trusty apprentice. to get decent U values. I was going for 100mm wood fibre, 8*2 with Frametherm 32 OSB, then service cavity etc. The design is simple to reduce costs. walls plus gables are around 112 M2. when you add the cost of timber / OSB battens and then the inflated costs of Frametherm32 and wood fibre your hitting 13K without thinking about vapour barriers / breather membranes battens etc. I've only had two quotes so far. but 10.6K delivered, this includes ICF for the strip footing, and a U of 0.13 with poly steel (this is the standard block with 100mm EPS EWI) obviously need to add to this Concrete,, pump and rebar but its starting to look favourable.

Has anybody had experience with these blocks? https://polysteel.co.uk/ I'm starting looking at other options for my planned timber frame build, as the increased insulation costs are making ICF look more affordable. (possibly cheaper). These are UK made, and have a steel web which looks substantial. The online available information is limited, and leaves me a lot of questions.

I've just had the following costs from Econekt 300mm Elements, 150mm concrete core - 0.19W/m2K 112 m2 £ 58.95 £ 6,602.40 Upgrade from Prince to King and a u value of 0.15W/m2K would be £15.34/m2 so circa £2,040 up. Upgrade from Prince to Super King and a u value of 0.11W/m2K would be £25.06/m2 so circa £3,332 up. Problem with these was delivery charge to my location.....

CW Berry?